Clarification on RC4558 pinout

[O]

I have this schem snippet and I'm a little confused with the pinout. Does it make sense to anyone? Shouldn't the (+) be connected to the input and not to ground?

As far as my understanding goes,
(-) is pin #2
(+) is pin #3
Pin #4 connects to Vccn
Pin #1 connects to D4
Pin #8 connects to Vcc

Is this right? Somehow, the pinouts don't jive with how a normal 4558 chip connects (at least not according to the schem)

Help?

[aziltz]

If thats just a regular old op-amp, that connection is ok, that's an inverting amplifier with negative feedback circuit (please correct me if i'm wrong).


Basically with op-amps, input can go to + or - , it just depends on how you set up the rest of the circuit.
check out  http://www.generalguitargadgets.com/richardo/distortion/
for different op-amp overdrive circuits.

Also, the way the op-amp is represented in that picture, the + and - and such don't correspond to a specific pin.  That schematic says nothing about what pin is which connection, normally (i think you are right here) - is pin 2, + is pin 3 like you stated.

[O]

That was one of the reasons why I was confused... I can figure out which pins go to power, but I'm not too sure about the other ones 

[cd]

Your example is using a bipolar supply.  That's why the + input is grounded.

[O]

Your example is using a bipolar supply.  That's why the + input is grounded.

Uggg... maybe I should just try to make a layout for this schem in a few months. I would post the complete schematic, but I don't want to get in trouble (the owner posts here sometimes).

[aziltz]

I havent worked with the 4558 yet.  but from what i know with 741s ( i think they are all the same), pin 6 is output, thats what would go to the diode.
pin 2 is (-), pin 3 is (+).
7 goes to +Vcc
4 to -Vcc or (Vccn)

If i'm confusing you more, ignore me, b.c then i probalby don't understand what youre asking.  Its my first time trying to answer a question.

[O]

I'm think I'll breadboard this first, just to make sure its all going to work. Thanks for all the help, aziltz & CD.

[Doug_H]

I have this schem snippet and I'm a little confused with the pinout. Does it make sense to anyone? Shouldn't the (+) be connected to the input and not to ground?

As far as my understanding goes,
(-) is pin #2
(+) is pin #3
Pin #4 connects to Vccn
Pin #1 connects to D4
Pin #8 connects to Vcc

Is this right? Somehow, the pinouts don't jive with how a normal 4558 chip connects (at least not according to the schem)

Help?

http://www.datasheetarchive.com/search.php?q=4558&sType=part&ExactDS=Starts

[O]

Thanks for that link, Doug... it sure did help.

I threw something together to see if anyone can verify it based on the little schem snippet. Is it right?

[O]

Bumpity bump

[Ge_Whiz]

The two main issues here are:

1. Your signature graphic is large and annoying, and
2. The 741 is a single op-amp. The 4558 is a dual op-amp and therefore has a different pin-out, though similar to most other dual op-amps.

[aziltz]

My bad, i figured that out this week.

apologies.